Species ca. 20 (6 in the flora): North America, Mexico, West Indies, Central America, South America.

The species of Argyrochosma traditionally have been assigned to either Notholaena or Pellaea . Comparative studies (M. D. Windham 1987) have revealed that members of Argyrochosma are not closely related to Notholaena as typified by N . trichomanoides (Linnaeus) Desvaux. The two genera show consistent differences in stem and leaf morphology, sporangial distribution, spore color and ornamentation, chromosome base number, gametophyte morphology, and chemical composition of the farina.

Argyrochosma is more closely related to Pellaea (M. D. Windham 1987) and members of these genera are occasionally confused. These two groups are easily distinguished, however, based on the presence or absence of farina, leaf segment size and shape, and characteristics of the stem scales and leaf margins. In addition, all species of Argyrochosma thus far examined have a chromosome number based on x = 27, unique among cheilanthoid ferns. These differences suggest that Argyrochosma is monophyletic and worthy of recognition as a distinct genus.